Speed reducer



Jan. 19, 1954 w. E. AMBEBG SPEED REDUCER 5 Sheets-Sheet 1 Filed Oct. 29, 1951 INVENToR.

f'- Z3 '#5 i7 @M15/@wen w. E. AMBERG Jan. 19, 1954 SPEED REDUCER 5 Sheets-heet4 2 Filed oct. 29, 1951 IN VEN TOR.

W. AMBERG lSPEED REDUCER Jan. 19, 1954 Filed Oct. 29, 1951 w. m m m W. E. AMBERG SPEED REDUGBR Jan. 19, 1954 5 Sheets-Sheet 4. l

Filed Oct. 29,k 1951 M Z/INVENTOR.

7g @a e 55 Jan. 19, 1954 w, E AMBER@ 2,666,345

SPEED REDUCER Filed Oct. 29, 1951 5 Sheets-Sheet 5 gi' 135 131 1334A- Z3 jg Ja, raL j pair of-wh'e" Patented Jan. 19, 1954 Thisinvention-.relatestoaspeedreducers:

The principal object of this ginventionviisV-toprovide `animproijedfsneed reducer of anintemal ringfy orbitalf-=motionrtypef'fwherein *therecis providedanimprovedzhaiiiess between the eccentric and concentric emotionsthereofrwhereinlarge speed reduction nat'iosfflareeobtained::with a minir'n-um fof-moving; Fpants inea-Junit Iof.l comparatively small dimensions, wherein vibrationsfintheeunit arernaintainedf tffaffmmimm, Iwherein ,large loads/and torque 'are readily!"handied-y wherein uniformtorque--f-andirspeed'- relations'` between.; the input and output:endsfofthespeed reducer-are obtainedrwhereinlfinternalffresistance is;A maintained at af"rr'1`ininiumto eprolwee high; efeiency.. wherein vmaiz-infact withiextreinely close tolerances-.isfnot require ,i1-andwhereinfmanufaeturing costs are maintained at a mi'nimnm.

Briefly; the Speedfredueer. ot this invention 1includesl aninternalring member "andvapair of connected oppose veoentricsrotatable. about an axis concentric" wi the-eentral` axisf of the 'internal ring member. l"fAtpairofmflieelsmf smalierfni` arneter than the internal ring member. are' carried by the' e'ccen'trist :opposingfperipheral ldriv'ing contactwitli the'fnternal'ringv` member. #Rotation of the eccentris causes orbitali-movementSoi-the about'fthecentral axis :ot fthe' 1internal ring? ernberv ndrelative rotatiorigbetween the lpair offwheelsand the internal ringmember. Becausevv of thisfoppsed? and ba1ncedfarrang'ement; vibration aintaiifxed'ata minixnurnand the axes of rotation the "'eceentrics isautoma-tically centered :with vrespectftdthe Vceni'iralax-isE of theiinternalfringxnember.

An intermediate member is disposed between the Vpair of trhfeels I`1d-"-Whppletreedriving-nnections" are provide between the Vy'pair of wheels and the'internieditcniember. LThese Whippletree driving-conne ons antoni'aticf:al-lycincontri-u ca-lly vponsitionfthe?,inteiiiditelexhb-'with 'e- 'spelct to @the 'centrali'vaiiis 'jf' of ithefinternal f3 ring member'A to provide' 'inpletelyev-balaneedl-arrangement. r`Thesefishippletieeleonneotiiie'-also establish a positive and uniform driving relation v fac clude -afgplurality of Aopenings in the nature of sockets-ineach off-these elements, the openings being correspondingly nlocated with respectto their respective central axes. "A plurality of whippletreelevrers arecarried 'in these openings andextendbetween the pair of wheels and -theintermeditatemembers. As the wheels are orbitally moved about the centralaxisof the internal 'ring member by the Aacceritrics,l 180 -angular "degrees oui-, ofA phase witheach other, v'the endsv ofY the wh-ippletreelevers are valso moved 180 angular 'degreresoutof phase; with'each other through true circles. vThew-hippletree levers are, therefore, so moved orbital, fashion as to generate double cones with the-apices-theref at'the center points of the whippletree levers, thesev center points accordingly being radially Yfixed, with respect to. the central 'axis of--the internal ring member. The intermediate n'mernber being carried'by the center points' of y the whippletreeV levers is thus automaticallyfcentered with. respect' to the central axis of the internal ringmember. FF.a'c'h of these Whippletreeleversin their orbital motion at all times andrin-all positions establish'a positivefancl uniform driving relation [between the pair bf wheeisand the inrtermediatemember so that uniform torque andspeed-transmissin' is provided.

In one Vform of this invention 'the internal 'ring member-is held stationary l'so that the intermedialte 'member vis "rotatedat thev uniform 'reduced speodaboiitvt'hecentral'aiiis 'of the internal ring member. Hereu'the pure rotary motin' of the 'in-'- ter-mediate member -isV transmitteol` through" 'the connecting means'carriedthereby '1n another formff this invention'fthe"'intermediate member ish'el'd 'stationary' b`y' the connectingmeans so thattheinternal ring member Vis rotated' at the uniform V"redued vspeed about its centralI axis*- Here` theiteral ring'rnenber may' take theform or adrivepuiy of the like.

To provide'for'ertra heavy'dty, that'is' where high torque loads are involved, a plurality of speed reducer `units, constructed' as "described above, may'be'compoundedimparano. Here meramentrcs Yof theriitsareconne'cted together for operation in niso'nj the' internal ring members' conneeted together and" the intermediate" members connected together. This' parallel AYcompounding of the" "speed'redi'icer units l-increases*the torque load trans.missie'rfbut notthe speed reduction. By co'mpo'unding"lla` plurality of "f Sp'ee'd'reducer units 'in seri'esf"multipe' speed reduction' may fbe bta'in'ed. There, the li-internal firing lmembers would be connected together-land held stationary to Acause'vr rotation-"ofthe intermediate `Vmembers., 'and theintermediate member of f one f unitwould bei connected to @they eccentrcs A of 'the next succeeding-unit. `'Lhusz-the output offene unit would -form thefinputor Athe jnext succeeding unitv to providefmultiple speed reductionY of almetiny desired degree. Of course, the speed reducer units may be of the same or differing sizes in these arrangements. These compoundings of units for these purposes also form features of this invenu tion.

The speed reducers of this invention may be of the gear type or of the friction type and combinations thereof and all types are contemplated herein. In the gear type, the internal ring meinber takes the form of an internal ring gear member and the pair of wheels takes the form of a pair of gear wheels in opposing peripheral meshing contact with the internal ring gear member. The meshing gear teeth provide a positive interlocking driving relationship to cause relative rotation because the gear wheels and the internal ring gear member as the gear wheels are orbitally moved by the eccentrics.

In the friction type speed reducer, the internal ring member takes the form of an internal friction ring member and the pair of wheels takes the form of a pair of friction wheels in opposing peripheral rolling frictional driving contact with the internal friction ring member. The engaging surfaces of the friction Wheels and the internal friction ring member may be of any desired material or oi any desired shape, such as a plane surface, a V-tongue and groove surface or the like, depending upon the rolling friction value desired. In the friction type speed reducer the rotatable eccentrics are preferably arranged so that they may move radially outwardly in opposite directions to maintain the peripheral rolling frictional driving contact between the friction wheels and the internal friction ring member. This maintains the desired driving Contact and hence the driving relation therebetween and compensates for wear and inaccuracy in the manufacture of the parts. Suitable preloading means, such as spring means, may be provided for preloading or biasing radially outwardly the eccentrics and hence the friction wheels into rolling frictional driving contact with the inter nal friction ring member. As the friction wheels are orbitally moved by the eccentrics, centrifugal force may also act upon the friction wheels to maintain the driving contact and also form a part of the preloading. The rolling friction value may be regulated to any desired value by proper arrangement of the preloading means, and preloading is obtained without imposing any substantial resistance to the operation of the speed reducer. In other words, the preloading of the friction wheels in this manner has substantially no effect upon the torque load transmission.

rThis friction type speed reducer has a further attribute in that when the torque load increases above a predetermined value, the rolling friction drive between the friction wheels and the internal friction ring member may be caused to slip, thereby providing the speed reducer with an automatic load responsive clutch action. The point at which this declutching action takes place may be regulated by the spring means which radially moves the eccentrics in opposite directions. Novel means are also provided for correlating and driving the eccentrics.

Further objects of this invention reside in the details of construction of the speed reducers of this invention and in the cooperative relationships between the component parts thereof.

Other objects and advantages of this invention will become apparent to those skilled in the 4 art upon reference to the accompanying specifi-a cation, claims and drawings, in which:

Fig. 1 is a vertical sectional view of one form of this invention and taken substantially along the line I-I of Fig. 2;

Figs. 2, 3, 4 and 5 are vertical sectional views taken substantially along the lines 2 2, 3 3, 4 4 and 5 5, respectively, of Fig. 1;

Fig. 6 is a vertical sectional View of another form of this invention;

Fig. 7 is a vertical sectional view of a further form of this invention wherein a plurality of speed reducer units are compounded in series for multiple speed reduction;

Figs. 8 and 9 are vertical sectional views taken substantially along the lines 8 8 and 9 9, respectively, of Fig. 7;

Fig. 10 is a vertical sectional view of still an' other form of this invention wherein the plu-V rality of speed reducer units are compounded in parallel for high torque load transmission;

Figs. 11 and 12 are vertical sectional views taken substantially along the lines Il il and ifi-l2 of Fig. 10;

Fig. 13 is a vertical sectional View of another form of this invention, wherein a plurality of friction type speed reducer units are compounded lin series for multiple speed reduction;

Fig. 14 is a vertical sectional view taken substantially along the line I4 i4 of Fig. 13;

Fig. 15 is a plan view of the shaft or tting for rotating the eccentrics of the first speed reducer unit of Fig. 13;

Fig. 16 is a horizontal sectional view through the connecting member for rotating the eccentrics of the second speed reducer unit of Fig. 13;

Figs. 17 and 18 are perspective views of the two eccentrics utilized in the first speed reducer unit of Fig. 13;

Fig. 19 is an enlarged vertical sectional view through the assembled eccentrics and taken substantially along the line lil-i9 of Fig. 20;

Fig. 20 is a vertical sectional view taken substantially along the line 2li-2i) of Fig. 19;

Fig. 21 is a horizontal sectional View taken substantially along the line 2 I 2l of Fig. 19;

Fig. 22 is a vertical sectional view of still a further form of this invention, wherein a plurality of friction type speed reducer units are compounded in parallelV for high torque transmission;

Fig. v23 is a vertical sectional view taken substantially along the line 23 23 of Fig. 22;

Fig. 24 is a partial sectional View taken substantially along the line 2li-2li of Fig. 23;

Fig. 25 is a partial sectional view taken substantially along the line 25-25 of Fig. 23; and

Fig. 26 is an exploded perspective view of the eccentrics of the first speed reducer unit of Fig. 22.Y Y

Referring rst to Figs. 1 to 5 of the drawing, a gear type speed reducer is generally designated at I0. It includes an internal ring member .ll in the form of an internal ring gear member, having gear teeth l2. `This internal ring member is stationariiy mounted in any suitable man-- ner and it has a central axis designated at I3. A rotatable shaft 5; has its axis of rotation con-- centric with the central axis I3 of the internal ring gear member I l and it carries a pair of opposed eccentrics VIt and Il. Thus, as the shaft I5is rotated the pair of opposed eccentrics rotate about the central axis I3.

Theeccentric l rotatably carries a wheel IS and the eccentric I7 rotatably carries a wheel accesa:

it,A th'ese-.vvheels`J leanezcteig the-*former gear--fwheels-'havinggearteeth 2l:l and22; re-

thel gear teeth or the internal ringv gear Iinem'- ber. and I-'I impart'orbital movement to the pair yof gear .wheels I9# and- 291 abouty thecentral L axis- I3- ofthe internal -ringgearmember I I Because the internal ringy gear member IVIY is-stationary and because 'or the peripheral drivingvcontactbetweenV thegear wheels I9 vandfl! and-the in'- ternal-rnggear member II, the pair of gear Wheels I9'1and-2Ilare caused,- also; to rotate aboutVv their own axes 23 and'2f4, respectively,n at'fa re duced speed as comparedto the speed of rotation of the shaft I5; The difference between the speed of rotation ofthe shaft I5A andjthespeed of, rotation of the gear-wheels I9and 2!)y about' 20v-and their operatingfveccentrics I6 and I1 are diametrically oppositelylocated a completely balanced arrangement` is provided to maintain vibration at a minimum-and theY axis of rotation of thehshaft I and eccentrics I'and I'I is automatically centered with respect to the cen'- tral axis I Sofithe internal ring gear -member II.

An intermediatemember26-is disposed between the pair of gearfwh'eelsIB and 20 and whippletree drivingA connections are provided between the pairof VgearWheelsa-nd this intermediate member. connections the gearW'h-e'els I9 and 20- and the intermediate member-*26 `are provided with a plurality of openings 21, 28 and 29; respectively, in the nature of sockets.- Theseopeningsfare correspondingly located with respect to the'central axes of the gear wheels I9ian-d'20 and the intermediate-member 26,; In the speed reducer, as here illustrated, the Agear Wheels and intermediate. member-are Vprovided with three such socket type openings which-are all equally spaced from the central axisof-each element. A plu'- ralityfof whippletreeflevers-3l); three levers as here illustrated, are located in the socket type openings 2l, 23and 29.`y whippletree levers 30 are located within the gear Wheels I9 and 2U and the'center-Of the levers 39 are located in the intermediate member 26.'`

As theL gear wheels I9 and r2l) -are orbitally moved about the central axis I3 of the internal ring gear Vmember II by the eccentrics, 180 angular degrees out of -phase'with' each other; the ends of the Whipple tree leversy 3l) `are also'moved ISOang'ular degrees out of phase with'e'ach other through true .circles havingyradii corresponding toithe amount of Ve'x'centricity Yofthe eccentrics IG and I'I.` The whipplfetree-levers 30vbeing so moved. in this .orbitalfashion generate double cones Awiththeapices thereofv at the center points of thewhippletreelevers.l These center points which are .wi-thin' the intermediate member 26 are therefore .radiallyxedwith respectto the central'axis-I-S'of the internal ring gear membery H.. Sincefthe @intermediate memberZB is; carried.'` vby *thev center peints of the whippletreev As the shaft i5' rotates,-the-eceentrics I6 To provide these whippletree The.l ends of thesev revers so; itis mcanismes-uy'camerali-.waa respect tothe central axis I3` offV the internal'- ring'gear member II. Each offthese'whippletree.

levers 39; in theirlorbital motion atv all times and in all positions-festablisl'a'positive and uni= form driving relation between the pair 'ofi gear Wheels I9 and 2U1andlth'einter-mediate "member with uniform .torque and 'speed-as the ygear Wheels I9handf20 are rotatedn-abjtitltheir respectiveaxes. The whippletree levers arel made vspherical in configuration'where'they contact the gearwheel's I9- and 20 yand the-intermediate ynie'rnb'er- 2t ac*- curately to maintain thisV` uniform relation. Briefly, these whippletree driving connections. automatically coneentrica-lly position the inter-V mediatevmember v2tfwitl-1 resiziecti to the central axis I3' ofthe internal ringfgear member IIt'O provide a completely balanced arrangement. They also establish a positive "anduniform-drivr ing relation between the pair of wheels I9 and Zit-and the intermediatefmernber 2Bto produce uniform rotation of the intermediate member 2t about the central axis I3.

In order to take off-the unifrmlrotating mo*- tion of the intermediatefmeinber 2B;- connecting means are securedtherete.- As-here illustrated,

the connecting means omprisesy thre'evpi'n's I32 which are secured to the ebiineetng member 2t and which extend-threngh` enlarged penings 33 formed in the gear wheel-2i):r The enlarged open ings 33 are made suiciently large so that the pins 32 will in no way interferef'withthe orbit-a1 motion of the gear wheel29z' VIf desired tli'e's'e pins may be utilized for operating a' shaft 3'."

ceived in holesy 34 of Va v'flangedcoupl-'ing Y535 `whibli may be secured as byHakeyBB-ite the l,shaft 3i.

Inthe form of the inventiondes'cribedabove the ring gear member II is iadef stationary and the intermediate niernb'erZGfiSdrivenat'reduced speeds, the reducedlspeed motin beingltrans-- mitted by the cormect'ing'means` including the pins 32. stationary then the internal ringgear member II will be driven at the--reducedspeed.A Such' an arrangement isillus'trated iI--Ilig 6, wherein they of the gearwheels I9andi20; the gear wheels' being driven'l byv the eccentries I 6 andf I I upon rotationof the motor'shaft |55 To hold-"sta tionary the intermediate-member'rZ the icon'- necting means in-the form ofpins 43 are secured to the intermediateA member' 26j and f extend through enlarged openings 4'4 inthe gear v'vlieell I 9 and maybe received in' suitable holes 'de in the casing of the motor 4I'. Here", as the eccen= tries I6 and I1 are rotated,-thegear wheels i9 and 20 are orbitally movedbut since theyare prevented from rotating about' their own respective axes by the stationaryintermediate member 26, the infernalY ring member or' pulley 42' is thereY upon driven 'at reduced speeds. The' manner of operation and thevar'ious features ofthe speed reducer 40 of Fig. 6 are substantially the same as those of the -speed 'reducer I0' 'of Figs. l .toi 5 andi-therefore, a further description is 7not ecnsidered necessary.

1n Figs. v ne 9 therein discis'ed intieme If the intermediate meinbe ZSS lheld' duction speed reducer generally designated at 50 having two speed reducer units connected in series for producing multiple speed reduction. The two speed reducer units are the same as that described above in connection with Figs. 1 to 5 and like reference characters have been utilized for like parts. The rst speed reducer unit, that is the one on the input side, has identical reference characters while the second speed reducer, that is the one on the output side, has the same reference characters, with the addition f theY letter a. While two speed reducer units have been shown for purposes of illustration, of course, any number' of serially connected units may be utilized. Here the stationary internal ring gear member II of the rst unit is connected to, as by integrally joining with, the internal ring gear member I Ia of the second unit. The input shaft I5 drives the intermediate member 26 of the first unit in the manner described above. The pins 32 secured to the intermediate member 26 of the first unit and forming the connecting means therefor extend into openings in a connecting member 5I secured to the shaft Ia of the second unit. In this way the rotation of the intermediate member 26 of the rst unit is transmitted to the eccentric shaft I5a of the second unit. The intermediate member a 0f the second unit drives the output shaft 31 through the connecting pins 32a. There are thus provided series connected units for obtaining two stages of speed Y reduction.

In Figs. 10 to 12 there is disclosed a heavy duty speed reducer generally designated at 55, including two speed reducer units compounded in parallel for producing high torque load operation. Here there Vis only a single stage of speed reduction. The speed reducer units and the operation thereof are like those discussed above in connection with Figs. 1 to 5 and like reference characters have been utilized for like parts, the first unit having identical reference characters and the second unit having the same reference characters followed by the letter a. While two units have been disclosed, of course, any number of units may be compounded. In this arrangement the internal ring gear members I I and I ic of the two units are connected together as by integrally joining the same. vThe input shaftV I5 drives all of the eccentrics I6, I1, Ilia and I1@ of both units. The intermediate members 26 and 26a of the two units are connected together by the connecting pins 32, which may also serve to transmit the rotary motion to the output shaft 31. Here, as in the case of the multiple reduction speed reducer 50, Figs. 1 to 9, the diameters and sizes of the gear wheels and internal ring gear members have been shown to be the same in the two units thereof. These dimensions and sizes may be different in the two Vunits without altering the end results. Any suitable size and dimensions for a particular application may be utilized. In fact, in the multiple reduction speed reducer of Figs. '1 to 9 it may be desirable to make the gear wheels and internal gear member of the second or output unit of greater size and dimensions for here the operating speeds are consid-v erably less than in the first or input unit and greater torque loads must be carried.

In Figs. 13 to 2l there is generally designated at 66 a speed reducer of the friction type having a plurality of friction type speed reducer units compounded in series for obtaining multiple speed reduction. The multiple reduction friction type speed reducer 60 includes an internal ring member 6I in` the form of a casing, having a cylindrical internal friction surface 62 and an internal cylindrical friction surface 63 which are concentric with the central axis 64 of the internal ring member. The internal friction surfaces 62 and 63 of the internal ring member 8i may be separated by a partition formed of a split ring 65 received in a groove.

The first or input speed reducer unit includes a pair of wheels 65 and 51 in the form of friction wheels which are in opposing peripheral rolling frictional driving contact with the internal friction surface t2 of the internal friction ring member Si, these friction wheels 66 and 51 being 180 degrees out of phase with each other. The friction wheels 65 and t1 are moved orbitally about the central axis Ed of the internal friction ring member si through anti-friction bearings e8 and 5%, respectively, by means of eccentrics 1@ and 1i, respectively. rThese wheels 66 and 61 so moved by the eccentrics 1t and 1i operate automatically to position the eccentrics 1t and 1i for rotation about the central axis te of the internal friction Yring member 5I, these eccentrics 'iii and 1I also being 180 degrees out of phase with respect to each other.V

The eccentrics 1t and 1I are illustrated in more detail in Figs. 17 to 21. The eccentric 1i! is provided with a pair of projections 12 and 13, having spring seat shoulders 1li and 15, respecu tively, and the eccentric is provided with a groove 1S between the projections 12 and 13. The eccentric 153 also has a pair of internal side surfaces 11 and 16. Gn the side of the eccentric opposite to the projections 12 and 13 there is provided a projecting tongue 19 having recesses Se and on each side of the tongue 19. The eccentric "si is of identical construction, having a pair of projections 83 and 84 provided with spring seat shoulders S5 and 86, a groove S1 between the projections $3 and Sd, internal side surfaces 88 and t9, a projecting tongue @il and recesses si and 92 on each side of the tongue Bil. The two eccentrics iii and 1I are assembled together with the projecting tongues 19 and 9@ received in the grooves 81 and 16, respectively, and with the projections 12 and 13 and the projections 33 and Slt received inthe recesses 9i and 92 and in the recesses SI and 8i?, respectively. The tongues and grooves on the two eccentrics engage with each other for coupling the eccentrios together for rotation in unison, but they afford outward radial movement of the eccentrics in opposite directions from their axis of rotation. The springseat shoulders 11i, 15 and 85, 86 of the two eccentrics 10 and 1I form opposed overlapping shoulders for receiving therebetween a compression spring 95 which resiliently urges the eccentrics 10 and 1I radially outwardly in opposite directions from their axis of rotation. Thus, as the eccentrics 1@ and 1I are rotated the friction wheels St and 51 are orbitally moved Vabout the central axis 61S. Since the coupling together of the two eccentrics iii and 1I permits radial outward movement thereof in opposite directions, the friction wheels 66 and 61 are maintained Vin opposing peripheral rolling fricticnal driving contact with the internal surface 62 of the friction ring BI and this is true regardless of wear between the wheels and the internal friction ring or slight inaccuracies in the manufacture thereof. The wheels 63 and 61 may be maintained in this frictional driving contact in part by centrifugal force and by the action of the compression spring 95 acting betweeiri the?V overlapping Shelli-ders; ther tw'c; ec- .Ycexi-tricsz` '13h-'ef rolling.r frictionmaluef between the wheels' anclzlthei internali fi'ictioiia'l 'ring member may be regulatedito.anwdesiredivalues byzproper a selection of the'.y compression springcSi andzw'this A may be" doneI without.. imposing any` -`y substantial resistance. to the: overall!` operation. ofstlieaspeed reducer; Aisa further.Z attribute?off"thissifriction typersp'eed reducen'.ther'rcllirrgV friction; drivel-between'. thefiriction wheels'. and the: interna-1.V fricthe torque load increases-'aborefjar. predetermined value? and. therefore;.f provid-esi thefspeedfreducer with aniautbmaticfloadsresponsivetclutcmaction.

AThe 'point'4` at: which thef clutching action.A takes 'placer maybe'` regulatedf. by` the:Y proper selection of the spring-I 95 Whichrradially lrhovea'tiie'fe'ecentrics 'I0 and Hz ini the'oppositef directions..

As inthe previous forms;oiftheiinvention; an

`inte'rmediaterv member' -sit l is* interpsedif between ithe airictiorr Wheels:- ir and: 67g;Y this:l intermediate member '91sv being1concentricallyfsupipctediV and rotated: about; ithe centralraxisf`641rby Whippltree levers 93 in the-manner' ei'iplaineda'aboye. Here, o for A*purposes ofJ illustration; Vthere:isishownz to.' bie `4SifX Whippletreef levers; i9 8v Whichaierreceivedz'in suitable socket-'like openingsirrv the. friction Awheels |56y 'andi-6271- a-ndi theY intermediate member -9'1 'thef 'whippletreei .leversz 9,8: being@ spherical. Tat

' the points whereftheyfcontact tire-wheelsfandz inf yterxriediatev member... Tlius;. asthe'wheelsf 6&- and B1 are orbitali-y: moved' about.l theeerrtrai.axisi 6.4 andlrotate'd'faboutttlieiif respectiver axes, the: initernediate` memberff'r ,is concentricaflly rotated atv reducedi:speedfaaboutthe' centrale axis. `'6:4.

The'. pure -'rotary motion for.' the intermediate member-91de(transmittedi yby@connecting 'means Y `'Sueir as pinsu? received in'holes: ini'the' i'rrter` :mediate member:"it-"r, extending .I-through; lenlarged holes |50 iirtherfrictionnwheel -E'If and lsecured to a'connectingfdevicerlllkf. lirthisrway the cerrne'cting'l device I tfisi'iirm'ly secured tof-the-intermediates` member 91'V and' rotates therewith; at fre- -duced l'speed about:the4`V central` axis-6.4.

The eccentrics' 'Nif-and. vM iof. the 'rst or: input unit may he driven vbsfa suitableetting: or 'shaft "|593, having et.k flattened: fend :HW which 4isi-bieiriroated'vto provide fin-gers ftfand'ilt.' f This shaft: .or iitting 'fi03is1lirisertedf-intoi vthe speedire- "ducer unit Valong ythe renti-a1: axis: E4 `the i'ingers 1&5 and g|06thereof beingwreceved in 'the openings# ftheeceeiitries 'l0 and' lisformed -by the internat side-surfaces 1L-,1158; 8a and-189 thereof. [The 'iin-gers rti'and intenter' these operrings:on` the 'opposite sides' oiithe' compressi'o'iir spring: '95', as .illustrated im more`r detail nin 'teitingthe same aboutithefcentral axis=64.

' To. guid'eithe positions-oitheeccentrics i1 t fand `iagfainst the eccentric? 1|r `finti-friction Vfrollers r'.iitiliirii for likepsrtsf'imse eccentrics ma and f ing member-IY iiii 'to providemultiplelspeed'i reducmail off the secondi-speed reducerunit are. drieen t-lie 'connectingE member' |201 and, 'int this-respect, the connectingmemberd 0 I iisfprovide'd with mem'ber"9Iaf.I is:` driven -Y at: a reducedsi'eedI with respectrto -thef speed or?rotation@y orf-the connecttion. This-reduoed speed-rotary. motion 'off the intermediate.: member 91uk is transmitted by means 'of fconnecting means including a- `plurality vof 'pinsf'f securedi tothe intermediate inem-ber 93a and exten-ding through openings Ifaf in the frictionwheel 61u. 'Iihe output end oftheV speed reducerf Gilclis: at lea-st" partially: closed byfarr an- ;-nularr plate' Iil 81 received inv ay suitable circular recess; formedin a.y iiange |`|19Jo1i theinternal fric- -tioniring-membenL This annular plateftlilzfis Vtatin'gWitlifthe-connecting'pins 99u. The 'confina@ also operate tomaintain thefeccentrics-'ia fand* 'Ifta improper -lorigitufolinalE position along-E the `cfehtral axis-'84?. As illustrated1 "the partsI ofthe y secorrdforoutput funit 'of Ythefspf-ie'd reducer-*610 Tmagy be-"of larger sizefand-dimensionsthan those 'ofthe vii-rstfor input unit since the second or cutputf unit,. whiler operatingy at slower speeds. does KYoperate: tovtransmitgg'reater torque loads. 'Of Lcourse;anyf-nunciioerof speed reducerunits-'rnaybe Y compounded in'series to obtainfthe desired de- 40 greefoffspeedreduction'.

The Speed reducer generaliy design-atedvat |39 Figs. 22r'tof24is also ofi the lfriction-type and is'fshown Ito-include aplurality of'l speed Yreducer units :compounded iii-'parallel for transmitting `largeV torque. `loads. 5Iierethe llieavyf *duty speed freducer'IIS, includes f an internal V friction 'ring member- -f3 I having internal cylindrical lfriction surfaces 32: and |32@ which are integrally kformed: together. These friction lsurfaees |532 and |32a have a common central axis -'|-33. One

:end 'ofithe speed reducer is vprovided with an enct'plate 134 `rlfxavn'gia bearing |35 for support- .eplate l'31'fhavingla bearing ISS for supporting Aan'outputshaft |39. The output shaft 139 has vaninternal bearing 14|! vfor journalling the inner e'ndioifthe input shaft |36.

`vBetween the'bear-ing's |35 and |40 the shaft "|36 is'squared as indicated at "|42. The first redu'cer unitiii'cludesa fpair of v"eccentrics |43 and l|44`mountedon the squared portion "|42 -of the shaft 136. in this 'respect the eccentric V|43 is v'provided ywith v'a substantially "rectangular fopening "|45 receiving thesduared portion '|42 of the shaft so that the' eccentric |43 is 'caused toro- 'tat/With the"`sha`ft, but yt is permitted :tO 'slide iradiai1y-outwaly therefrom. This eccentric |43 fisvfal'soprovidedwithfarpairfof shoulders |46 and y'I4-'IJ 'The rother*eccentric |44 'is -4likewise pro- 'vided v`with a substantially rectangular opening 148 for receiving the ISquared pi'a'rtio'ri |42 oi. the vshaft '|'35'in 'order to 4mcunt y'the A'eccentric |44 'for rotation l'with Athe shaft but yet rpermit radial `-rrlclmiernent of the1'eccentric ill-#outwardly from the shaft in the opposite direction. This eccentric |44 is also provided with shoulders |49 and |50 which overlap the shoulders. |46 and |41 of the eccentric |43 when the two eccentrics are assembled together. A pair of springs are located on opposite sides of the squared portion |42 of the shaft i3|i between the overlapping shoulders Ult, |41 and 49, |59, this spring operating to move the two eccentrics radially outwardly in opposite directions. These eccentrics are, therefore, rotated 180 degrees out of phase with each other and are spring biased outwardly.

The eccentric |43 carries a friction wheel |55 by means of anti-friction bearings |55 and, likewise, the eccentric |45 carries a friction wheel |53 by means of anti-friction bearings |51. The friction wheels |56 and |58 are also 180 angular degrees out of phase with respect to each other and are resiliently urged into opposed peripheral rolling frictional driving contact with the internal cylindrical surface |32 of the internal friction ring member |35. An intermediate member |65 is interposed between the two friction wheels |55 and |58 and is concentrically positioned and rotated about the central axis |33 by movement of the friction wheels |55` and |58 by means of whippletree levers itl in the same manner as described above in connection with the other forms of this invention.

The second speed reducer unit of the speed reducer |311 is the same as the rst speed reducer unit and operates in the same manner and like reference characters, with the addition of the letter a, have been utilized for like parts. Here the eccentrics |43a and |44a are secured in the same fashion to the squared portion |42 of the shaft 35 so that the two speed reducer units operate in parallel. The intermediate members it and |60@ of the two reducer units are connected together for simultaneous rotation about the central axis |33 by connecting pins |63, these connecting pins extending through enlarged openings |54 in the friction wheels |58 and |5811. To transmit the pure rotary motion of the intermediate members |60 and |60a to the output shaft |39, connecting pins |55 may be secured between the intermediate member lfia and a fiange |53 on the output shaft |39, these connecting pins |55 extending through enlarged openings |66 in the friction wheel |58a.

The friction type speed reducers illustrated in Figs, i3 to 26 operate in substantially the same way as do the gear type speed reducers illustrated in Figs. l to 12 in that they operate with uniform speed and torque transmission in performing their speed reducing functions and do so with a completely balanced construction, thereby maintaining vibration at an absolute minimum. In the gear type speed reducer there is a positive locking between the internal ring member and the wheels to provide a positive action. In the friction type unit there is a rolling frictional driving contact between the wheels and the inter# nal ring member but because of centrifugal force and the action of the spring means for separating the wheels in opposite directions, there is little or no slippage between the wheels and the internal ring member under normal speed and load conditions so that here, likewise, a positive driving action is also afforded. In the friction speed reducer, if the load should rise above a predetermined amount then slippage will occur between the wheels and the internal ring member so that the .speed reducer will operate also as an automatic load responsive clutch. The speed reducer of this invention in either the gear type or friction type, or both, may comprise a single unit or a plurality of units compounded in series or parallel depending upon the amount of speed reduction desired and the torque loads to be accommodated. Also, the speed reducer may be formed of both friction and gear type units as, for example, wherein the input unit would be a friction type where high speeds and low torques are present, and wherein the output unit may be of the gear type where relatively low speeds and high torque loads are present.

While for purposes of illustration several forms of this invention have been disclosed, other forms thereof may become apparent to those skilled in the art upon reference to this disclosure and, therefore, this invention is to be limited only by the scope of the appended claims.

I claim as my invention:

1. A speed reducer comprising, an internal ring member, a pair of connected opposed eccentrics rotatable about an axis concentric with the central axis of the internal ring member, a pair of spaced wheels of smaller diameter than the internalv ring member carried by the eccentrics in opposing peripheral driving contact with the internal ring member, rotation of said eccentrics causing orbital movement of said pair of wheels about the central axis of the internal ring member and relativev rotation between the pair of wheels and the internal ring member, an inter mediate member disposed between the pair of spaced wheels, and whippletree driving connections between the pair of spaced wheels and the intermediate member for concentrically positioning the intermediate member with respect to the central axis of the internal ring member and for establishing a driving relation between the pair of spaced wheels and the intermediate member .to produce relative rotation between the inter mediate member and the internal ring member.

2. A speed reducer comprising, an internal ring member, a pair of connected opposed eccentrics rotatable about an axis concentric with the cen-f tral axis of the internal ring member, a pair of' spaced wheels of smaller diameter than the interd nal ring member carried by the eccentrics opposing peripheral driving contact with the internal ring member, rotation of said eccentrics causing orbital movement of said pair of wheels about the central axis of the internal ring member and relative rotation between the pair of wheels and the internal ring member, an intermediate member disposed between the pair of spaced wheels, whippletree driving connections between the pair of spaced wheels and the intermediate member for concentrically positioning the intermediate member with respect to the central axis of the internal ring member and for establishing a driving relation between the pair of spaced wheels and the intermediate member to produce relative rotation between the intermediate member and the internal ring member, and connecting means extending through enlarged openings in at least one of the wheels and secured to the intermediate member.

3. A speed reducer comprising, a stationary internal ring member, a pair of connected opposed eccentrics rotatable about an axis concentric with the central axis of the internal ring member, a pair of spaced wheels of smaller diameter than the internal ring member carried by the eccentrics in opposing peripheral driving contact with the internal ring member, rotation of said eccentrics causing orbital movement of :femm Y 113 'r4 said. :pairrof .wv-he els about th'e entraL-eaxsadfdih the? intermediates; member: with.

about their respectives:l axes,s. fan-r intermediate securing.; the-e Wheelsi against, rotationsabout member disposed 'between a thepair:y ot' spaced theinresneetive aXe'sfto cause ,lrotationroff they inwh'eels; andWhippietreefdrivingmonnections:b'efrcs terri-ali'ringiifrr.em-ber:abcrutitefcerrtral-axis;` tween the vpair of spacedWheelsandfihevinter 7:,.Azspeedgrediicei.Comprising: internalring mediate: membe'rfiorf coneentrcal--lmA positioning member, a pair of conneeteifupposedeecerltrics theintermediatememberfwithfrespect[to thefcen'- rotatableaaboutpanxaieis ceneentriefwith triebentral axis of the internal ringimember-fandwfor traba-:iis voftlriee internalf ring member,v a pair rotatablydrivingtherintermediate member` asthe fle or spaced Wheel@of::smaller diameter than-b, the wheeisrotate about theirlrespectivefaxes.: internal-1 ring; memberffoarried-A-by; the.; ecoentrics 4L A Speed Tedurfmpl'sngsl aP-Statinary :inropphsingfperipheralgdriyingfcorrtaet' Withthe internalfringmembr;afparf Connected Opposed internal rings-member; rotation off said Leceenee'ce'ntrics Vrotatablefabout mmaxisconcentric with tribesfcausingzorbital; movementyofasaid pair., of

vthe tcentral Taxis fof" the viiiteriialfriiifg membtew'a 'f15 wheels;ab'oiitthezcentralaxis -ofi-ther*internalfring pair' of .'spacedvwh'efelsf oissmaller -idiainei';'errthan memben'andirelativefrotatioriz between: thefpairfof the intrnallg' Ilemb'ei'`-carriedz--bytheieCCBlllL -Wtieelslt-"andrthelinternals-ring membe1' ;an inter,- trics-Iin oppsingfperipherakidrivingcontaetiwth mediate? member fdisposedf between the pair of cetrics causinfglorbital movementofsaidrpairfoi 20 'the-r. Wheelszfand :the intermediate kmember-f and 'Wheels abolttiiefeeiitralfaxisofthefeinterrialring correspondingly located' with respect to theoenmember"androtationlof lsaid"Wheelsfaboitttlieir :tra-1i .axiswof each; thereof', and, a plurality '0f respective' axesy "an intermediate t'me'mbe1: diswhippletreei leversvcarriedfin the openings and 'ber about its central"aiisjairinterme' 'at ber disposed betiieenjth'eipair of-f'si heels,

and vin opposedVv periphefar 'd 'the'pair ofjwheelsQrotation 'of sa nfgimemeevan tneirfrespesmve means for se'ouririgfr'the; inter-inedl te m mbr withfr respect toitbecntral axisio'f each 'against rotation; an'dl -W ``i-1f3p1e1fireel 'e loris thereof* "-n'da pl-iiralityf whippletreeievers'oarbetween the pair"offfsjiiaicedt"Wheels-fandY l-iefiir- 730 'ri-"ed th' 'rieziizigs'fan' 'ei'tending'between the termediate member for oneerntricallly psitibh'- Igan-irmemtgfmdiatememing' the intermediate rriniberwith rspeet toithe yf'p'dsi-tiening- 't1-le intermedilcentral"axisv of vthe" interi/'1 "14 ririgf'rfnember and mbeijwithriespecttofthefcentral axis ofthe for vsecuring the' Wheels ""gai'stdrotatiiriabot their 'respective 1 a'Xs to Cause 'rota tween the pair of spaced wheels and the intermediate member for concentrically positioning the intermediate member with respect to the contrai axis of the internal ring member and for securing the wheels against rotation about their respective axes to cause rotation of the internal ring member about its central axis.

10. In a speed reducer having an internal ring member, a pair or wheels of smaller diameter than the internal ring member and a pair of rotating eccentrics for driving the pair of wheels in opposing peripheral driving contact with the internal ring member, an intermediate member disposed between the pair of wheels, a plurality of openings in each of the wheels and the intermediate member, and a plurality of whippletree levers carried in the openings and extending between the pair ci Wheels and the intermediate member for concentrically positioning the intermediate member with respect to the internal ring member and for establishing a driving relation between the pair of wheelsv and the intermediate member to produce relative rotation between the intermediate member and the internal ring member.

1l. In a speed reducer having an internal ring member, a pair of wheels of smaller diameter than the internal ring member and a pair of rotating eccentrics for driving the pair of wheels in opposing peripheral driving contact with the internal ring member, an intermediate member disposed between the pair of Wheels, a plurality of openings in each of the Wheels and the intermediate member, a plurality of whippletree levers carried in the openings and extending between the pair of wheels and the intermediate member for concentrically positioning the intermediate member with respect to the internal ring member and for establishing a driving relation between the pair of wheels and the intermediate member to produce relative rotation between the intermediate member and the internal ring member, and connecting means secured to the intermediate member and extending through enlarged openings in at least one of the wheels.

l2. A heavy duty speed reducer comprising, a plurality of speed reducer units, each including an internal ring member, a pair of wheels of smaller diameter than the internal ring member, a pair of rotating eccentrics for driving the pair oi wheels in opposing peripheral driving Contact with the internal ring member, an intermediate member disposed between the pair of wheels and whippletree connections between the pair of wheels and the intermediate member for concentrically positioning the intermediate member with respect to the internal ring member and for establishing a driving relation between the pair of wheels and the intermediate member to produce relative rotation between the intermediate member and the internal ring member, means for connecting together the internal ring members of all of the units, means for driving in unison the eccentrics of all of the units, and means for connecting together the intermediate members of all of the units.

i3. A multiple reduction speed reducer comprising, a plurality of speed reducer units, each including a stationary internal ring member, a pair of wheels of smaller diameter than the internal ring member, a pair of rotating eccentrics for driving the pair of wheels in opposing peripheral driving contact with the internal ring member, an intermediate member disposed between the pair of wheels and whippletree con- .nections between the pair of wheels and the intermediate member for concentrically positioning the intermediate member with respect to the internal ring member and for rotatably driving the intermediate member, means for connecting together the internal ring members of all ci the units, and means connected to the intermediate member of each unit for driving the eccentrics of a subsequent unit.

14. A heavy duty speed reducer comprising, a plurality of speed reducer units, each including `an internal ring member, a pair of wheels of smaller diameter than the internal ring member, a pair of rotating eccentrics for driving the pair of wheels in opposing peripheral driving Contact with the internal ring member, an intermediate member disposed between Lhe pair of wheels and Whppletree connections between the pair of Wheels and the intermediate member for concentrically positioning the intermediate member With respect to the internal ring member and for establishing a driving relation between the pair of wheels and the intermediate member to produce relative rotation between the intermediate member and the internal ring member, and connecting means secured to the intermediate members of all of the units and extending through enlarged openings in the wheels of all of the units.

15. A multiple reduction speed reducer comprising, a plurality of speed reducer units, each including a stationary internal ring member, a pair of wheels of smaller diameter than the internal ring member, a pair of rotating eccentrics for driving the pair of wheels in opposing peripheral driving contact with the internal ring member, an intermediate member disposed between the pair of wheels and whippletree connections between the pair of wheels and the intermediate member for concentrically positioning the intermediate member with respect to the internal ring member and for rotatably driving the intermediate member, means for connecting together the internal ring members of all of the units, and connecting means secured to the intermediate member of each unit and extending through enlarged openings in one of the wheels of that unit for driving the eccentrics of a subsequent unit, the connecting means of the last unit forming the output drive of the speed reducer* 16. A speed reducer comprising, an internal ring member, a pair of wheels of smaller diameter than the internal ring member, a pair of rotating eccentrics for driving the pair of wheels in opposing peripheral driving Contact with the internal ring member, an intermediate member disposed between the pair of wheels, and Whippletree connections between the pair of wheels and the intermediate member for concentrically positioning the intermediate member with respect to the internal ring member and for establishing a driving relation between the pair of wheels and the intermediate member to produce relative rotation between the intermediate member and the internal ring member.

17.'A speed reducer comprising, an internal ring member, a pair of wheels of smaller diameter than the internal ring member, a pair of rotating eccentrics for driving the pair of wheels in opposing peripheral driving contact with the internal ring member, an intermediate member disposed between the pair of wheels, whippletree connections between the pair of wheels and the intermediate member for concentrically positothe internal ring member and for establishing a driving relation between the pair of wheels and the intermediate member to produce relative rotation between the intermediate vmember Vand the internal ring member, and connecting means secured to the intermediate member and extending through enlarged openings in at least one of the wheels.

18. A gear type speed reducer comprising, an internal ring gear member, a pair of gear wheels of smaller diameter than the internal ring gear 'memben a pair of rotating eccentrics for driving the pair `of gear wheels in opposingl peripheral f meshing contact with the internal ring gear 'memben an intermediate member disposed between" the pair of gear wheels, and whippletree f connections between' the pair of 'gear wheels and the intermediate member for concentrically podiate member and the internal ring gear member. e

v19. A friction type speed reducer comprising,

^ f an internal friction ring member, a pair of friction wheels of smaller diameter than the internal friction ring member, a pair of rotating eccentrics for driving the pair of friction wheels in opposing' peripheral rolling frictional driving contact with the internal friction ring member, an intermediate memberdisposed between the pair of friction wheels, and whippletree connections between thepair of friction wheels and the intermediate member for concentrically positioning the intermediate member with respect tothe internal friction ring member and for establishing a driving relation between the pair of friction wheels and the intermediate member to produce-relative rotation between the intermediate member and the internal friction ring member.

20.In a friction type speed reducer, the combination of, an internal friction ring member, a pair of adjacent andv opposed eccentrics rotatable about an axis concentric with the central axis of the internal friction ring member and provided with overlapping shoulders, spring means between the overlapping shoulders for rea pair of adjacent and opposed eccentrics rotatable about an axis concentric with the central axis of the internal friction ring member, a pair of friction wheels of smaller diameter than the internal friction ring member carried by the eccentrics in opposing peripheral rolling frictional -driving contact withthe internal friction ring member, and means for urging the eccentrics radially outwardly in opposite directions from their axis of rotation for maintaining the peripheral rolling frictional driving contact between the friction wheels and the internal friction ring member.

22. In a friction type speed reducer, the combination of, an internal friction ring member,

#a pair of adjacent and opposed eccentrics rotat- "able about an axis concentric with the central axis of the internal friction ringmember, a pair of friction wheels of smaller diameter than the internal friction ring member carried by the eccentricsv in opposing peripheral rolling frictional driving contact with the internal friction ring member, and means for coupling the eccentrics together for rotation in unison but affording outward radial movement thereof in opposite directions from their axis of rotation for maintaining the peripheral rolling frictional driving contact between the friction wheels and the internal friction ring member.

' 23. Ina friction type speed reducer, the combination of, an internal friction ring member, a pair of adjacent and opposed eccentrics rotatable about an axis concentric with the central axis of the internal friction ring member, a pair vof friction-wheels of smaller diameter than the internal friction ring member carried by the eccentrics in opposing peripheral rolling frictional driving contact with the internal friction ring member, and a tongue and groove on each eccentric engaging with each other for coupling the eccentrics together for rotation in unison but affording outward radial movement thereof in Opposite directions from their axis of rotation for maintaining the peripheral rolling frictional driving contact between the friction wheels and the internal friction ring member.

24. In a friction type speed reducer, the cornbination of, an internal friction ring member, a pair of adjacent and opposed eccentrics rotatable about an axis concentric with the central axis of the internal friction ring member, a pair of friction wheels of smaller diameter than the internal friction ring member carried by the eccentrics in opposing peripheral rolling frictional driving contact with the internal friction ring and spring means between the overlapping shoulders for resiliently urging the eccentrics radialli7 outwardly to maintain the opposing peripheral rolling frictional driving contact between the friction wheels and the internal friction ring member.

25. In a friction type speed reducer, the combination of, an internal friction ring member, a drive shaft rotatable about an axis concentric with the central axis of the internal friction ring member, a, pair of adjacent and opposed eccentrics mounted on the drive shaft for rotation therewith but slidably radially movable in opposite directions from the axis of rotation, and a pair of friction wheels of smaller diameter than the internal friction ring member carried by the eccentrics in opposing peripheral rolling frictional driving contact with the internal friction ring member.

v 26. In a friction type speed reducer, the combination of, an internal friction ring membena drive shaft rotatable about an axis concentric with the central axis of the internal friction ring member, a pair of adjacent and opposed eccentrics mounted on the drive shaft for rotation therewith but slidably radially Amovable in opposite direc tions from the axis of rotation, a pair of friction wheels of smaller diameter than the internal friction ring member carried by the eccentrics in opposing peripheral rolling frictional driving contact with the internal friction ring member, and means for urging the eccentrics radiallyoutwardly in opposite directions from the axis of rotation for maintaining the peripheral rolling frictional driving contact between the friction wheels and the internal friction ring member.

27. In a friction type speed reducer, the combination of, an internal friction ring member, a drive shaft rotatable about an axis concentric with the central axis of the internal friction ring member, a pair of adjacent and opposed eccentrics mounted on the drive shaft for rotation therewith but slidably radially movable in opposite directions from .the axis of rotation, a pair of friction wheels of smaller diameter than the internal friction ring member carried Iby the eccentrics in opposing peripheral rolling frictional driving contact with the internal friction ring member, overlapping shoulders on the eccentrics, and spring means between the overlapping shoulders for resiliently urging the eccentrics radially outwardly in opposite directions from the axis .of rotation for maintaining the peripheral rolling frictional driving contact between the friction wheels and the internal friction ring member.

28. A friction type speed reducer comprising, an internal friction ring member, a pair of adjacent and opposed eccentrics rotatable about an axis concentric with the central axis of the internal friction ring member and provided with overlapping shoulders, spring means between the overlapping shoulders for resiliently urging the eccentrics radially outwardly in opposite directions from their axis of rotation, a pair of friction wheels of smaller diameter than the internal friction ring member carried by the eccentrics in opposing peripheral rolling frictional driving con- 'tact with Ythe internal friction ring member, an

intermediate member disposed between the pair of friction wheels, and whippletree connections between the pair of friction wheels and the intermediate member for concentrically positioningT the intermediate me-mber with respect to the internal friction ring member and for establishing a driving relation between the pair of friction wheels and the intermediate member to produce relative rotation between the intermediate member and 'the internal friction ring member.

29. A friction type speed reducer comprising,

an internal friction ring member, a `pair of adjacent and opposed eccentrics rotatable about an axis concentric with the central axis of the internal friction ring member, a pair of friction wheels of smaller diameter than the internal friction ring member carried by the eccentrics in opposing peripheral rolling frictional driving contact with the internal friction ring member, means for urging the eccentrics radially outwardly in opposite directions from their axis of rotation for maintaining the peripheral rolling frictional driving contact between the friction Wheels and the Ailltelrlal friction ring member, an intermediate member disposed between the pair of friction wheels, and whippletree connections between the pair of friction wheels and the intermediate member for concentrically positioning the intermediate member with respect to the internal friction ring member and for establishing a driving relation between the pair of friction wheels and the intermediate member to produce relative rotation between the intermediate member and the internal friction ring member.

30. A friction type speed reducer comprising, an internal friction ring member, a pair of adjacent and opposed eccentrics rotatable about an axis Vfriction ring member, a pair of friction wheels of smaller -diameter than the internal friction ring member carried by the eccentrics in opposing peripheral rolling frictional driving contact with the internal friction ringmember, means for coupling ythe eccentrics together for rotation in unison but affording outward radial movement thereof in opposite directions from their axis of rotation for maintaining the peripheral rolling frictional driving contact between the friction wheels and .the internal friction ring member, kan intermediate member .disposed between the pair of friction wheels, and whippletree connections between the pair of vfriction wheels and the intermediate-member for concentrically positioning the intermediate member with respect to the internal friction Vring member and for establishing a driving relation between the pair of friction wheels and the intermediate -member to :produce relative .rotation between the intermediate member and the internal friction ring member.

31. A friction type speed reducer comprising, an internal friction ring member., a pair of adjacent and opposed eccentrics rotatable about an axis concentric with the central axis of the internal friction ring member, a pair of friction wheels :of smaller diameter than the internal friction yring member carried by the eccentrics in opposing peripheral rolling frictional `driving contact with the internal friction ring member, a tongue and groove on each eccentric engaging with each other for coupling the eccentrics together for rotation in unison ibut affording 4outward radial movement thereof in opposite directions from their axis of rotation for maintaining the peripheral rolling frictional driving contact between the friction wheels and the internal friction ring member, an intermediate member disposed between the pair of friction wheels, and whippletree connections between the ipair 0f friction wheels and the intermediate member for concentrically positioning the intermediate member with respect to the internal friction ring member and for establishingV a driving relation between the pair of friction wheels and the intermediate member to produce relative rotation between the intermediate member and the internal friction ring member.

32. A friction type speed reducer comprising, an internal friction ring member, a pair of adjacent and opposed eccentrics rotatable about an axis concentric with the central axis of the internal friction ring member, a pair of friction wheels of smaller diameter than the internal friction ring Vmember carried by the eccentrics in opposing peripheral rolling frictional driving contact with the internal friction ring member, a

tongue and groove on each eccentric engaging with each other for coupling the eccentrics together for rotation in unison but affording outward radial movement thereof in opposite directions from their axis of rotation, a shoulder .on each eccentric overlapping the other, spring means between the overlapping shoulders for resiliently `urging the eccentrics radially outwardly 'to maintain'the opposing peripheral rolling frictional driving contact between the friction wheels and the internal friction ring member, an intermediate member disposed between the pair of friction wheels, and whippletree connections between the pair of friction wheels and the intermediate member for concentrically positioning the intermediate member with respect to the internal friction ring member and for establishing a driving relation between the pair of friction wheels and the intermediate member to produce relative rotation between the intermediate member and the internal friction ring member.

33. A friction type speed reducer comprising, an internal friction ring member, a drive shaft rotatable about an axis concentric with the central axis of the internal friction ring member, a pair of adjacent and opposed eccentrics mounted on the drive shaft for rotation therewith but slidably radially movable in opposite Idirections from the axis of rotation, a pair of friction wheels of smaller diameter than the internal friction ring member carried by the eccentrics in opposing peripheral rolling .frictional driving contact with the internal friction ring member, an intermediate member disposed between the -pair of friction wheels, and Whippletree connections between the pair ,of friction wheels and the intermediate member for concentrically positioning the intermediate member with respect to the internal friction ring member and for establishing a driving relation between the pair of friction wheels and the intermediate member to produce relative rotation between the intermediate member and the internal friction ring member.

34. A friction type speed reducer comprising, an internal friction ring member, a drive shaft rotatable about an axis concentric with the central axis of the internal friction ring member, a pair of adjacent and opposed eccentrics mounted on the drive shaft for rotation therewith but slidably radially movable in opposite directions from the axis of rotation, a pair of friction wheels of smaller diameter than the internal friction ring member carried by the eccentrics in opposing peripheral rolling frictional driving contact with the internal friction ring member, means for urging the eccentrics radially outwardly in opposite directions from the axis of rotation for maintaining the peripheral rolling frictional driving contact between the friction wheels and the internal friction ring member, an intermediate member disposed between the pair of friction wheels, anclwhippletree connections between the pair of friction wheels and the intermediate member for concentrically positioning the intermediate member with respect to the internal friction ring member and for establishing a driving relation between the pair of friction wheels and the intermediate member to produce relative rotation between the intermediate member and the internal friction ring member.

35. A friction type speed reducer comprising, an internal friction ring member, a drive shaft rotatable about an axis concentric with the central axis of the internal friction ring member, a pair of adjacent and opposed eccentrics mounted on the drive shaft for rotation therewith but slidably radially movable in opposite directions from the axis of rotation, a pair of friction wheels of smaller diameter than the internal friction ring member carried by the eccentrics in opposing peripheral rolling frictional driving contact with the internal friction ring member, overlapping shoulders on the eccentrics, spring means between the overlapping shoulders for resiliently urging the eccentrics radially outwardly in opposite directions from the axis of rotation for CIS maintaining the peripheral rolling frictional driving contact between the friction wheels and the internal friction ring member, an intermediate member disposed between the pair of friction wheels, and whippletree connections between the pair of friction wheels and the intermediate member for concentrically positioning the intermediate member with respect to the internal friction ring member and for establishing a driving relation between the pair of friction wheels and the intermediate member to produce relative rotation between the intermediate member and the internal friction ring member.

36. In a friction type speed reducer, the combination of, an internal friction ring member, a pair of adjacent and opposed eccentrics rotatable about an axis concentric with the central axis of the internal friction ring member, a pair of friction wheels of smaller diameter than the internal friction ring member carried by the eccentrics in opposing peripheral rolling frictional driving vcontact with the internal friction ring member, a tongue and groove'on each eccentric engaging with each other for coupling the eccentrics together for rotation in unison but affording outward radial movement thereof in opposite directions from their axis of rotation for maintaining the peripheral rolling frictional driving contact between the friction wheels and the internal friction ring member, and a pair of openings in each of the eccentrics for receiving a bifurcated end of a rotatable shaft for rotating the eccentrics.

37. In a friction type speed reducer, the combination of, an internal friction ring member, a pair of adjacent and opposed eccentrics rotatable about an axis concentric with the central axis of the internal friction ring member, a pair of friction wheels of smaller diameter than the internal friction ring member carried by the eccentrics in opposing peripheral rolling frictional driving contact with the internal friction ring member, a tongue and groove on each eccentric engaging with each other for coupling the eccentrics together for rotation in unison but affording outward radial movement thereof in opposite directions from their axis of rotation, a shoulder on each eccentric overlapping the other, spring means between the overlapping shoulders for resiliently urging the eccentrics radially outwardly to maintain the opposing peripheral rolling frictional driving Contact between the friction wheels and the internal friction ring member, and a pair of openings in each of the eccentrics for receiving a bifurcated end of a rotatable shaft for rotating the eccentrics.

WALTER E. AMBERG.

References Cited lin the file of this patent UNITED STATES PATENTS Number Name Date 449,900 Clemons Apr. 7, 1891 890,107 Van Decar` June 9, B 1,365,492 Hotlee Jan. 11, 1921 1,910,777 Soddy May 23, 1933 2,170,951 Perry Aug. 29, 1939 2,502,316 Erickson Mar. 28, 1950 2,508,121 McIver May 16, 1950 2,520,282 Henry Aug. 29, 1950 

